1. Technical Field
The present disclosure relates to a resonance suppression device.
2. Background Art
In recent years, renewable energy has gained popularity and large-scale wind farms provided with a large number of wind power generators have been constructed.
A wind power generator includes an (AC-DC) converter that converts the generated power into a direct current power, a (DC-AC) inverter that converts the direct current power into an alternating current power, and also a harmonic filter that removes a harmonic current generated by the inverter. However, where a wind power generator provided with a harmonic filter is connected (linked) to a power system, a resonance caused by the capacitance of the harmonic filter and the inductance of the power system or a transformer is generated and the output voltage can be unstable.
Accordingly, for example, Patent Literature 1 (FIG. 2) discloses an active filter for power that extracts a harmonic component contained in a load current by using a high-pass filter (HPF) and controls a power conversion device such as to cancel the harmonic component. Further, for example, Patent Literature 2 discloses a power conversion device in which a harmonic current is suppressed by correcting a current command value with a current correction value obtained by multiplying a current flowing from an alternating current power supply to a capacitor, or a harmonic component included in a voltage generated thereby, by a predetermined transfer function.
Patent Literature 1: Japanese Patent Application Publication No. H8-80052
Patent Literature 2: Japanese Patent Application Publication No. H11-32435
Patent Literature 3: Japanese Patent Application Publication No. 2003-174725